The present invention relates more particularly, but not exclusively, to a type of dispenser member which is commonly designated under the term “pusher-pump”. Such a designation is explained by the fact that the dispenser member includes a pusher forming not only a dispenser orifice, but also defining a portion of a fluid chamber in which the fluid is put under pressure selectively. In the case of a pump, the fluid chamber is a pump chamber. A characteristic of the pusher-pump resides in the fact that an inside surface of the generally substantially cylindrical pusher serves as a surface against which the piston moves in leaktight sliding contact, thereby selectively revealing the dispenser orifice. The piston is generally a piston of the differential type, which moves in response to a variation in the pressure of the fluid inside the chamber. The differential piston is different from the main piston, which is moved by actuating the pusher. Thus, in such a pusher-pump, there are both a differential piston and a main piston, which are displaceable in leaktight contact in respective cylinders. The main cylinder for the main piston may also be formed inside the pusher.
This applies, in particular, to the case of the pump described in document WO 97/23304. The pusher includes a press wall on which pressure is exerted by means of a finger in order to actuate the pusher. Furthermore, the pusher includes a skirt which extends downwards from the press wall. The skirt forms a first leaktight sliding cylinder for a differential piston and a main, second cylinder for the main piston of the pump. The differential piston is disassociated from the main piston. The differential piston is urged away from the press wall by a spring which serves both as a return spring and as a precompression spring. The cylinder in which the differential piston slides is formed with an outlet duct which leads to a nozzle fixed in a housing formed in the skirt of the pusher. The nozzle forms a dispenser orifice through which the fluid leaves the dispenser member. Furthermore, the housing formed in the skirt is provided with a swirl system which co-operates with the nozzle so as to cause the fluid to swirl before leaving through the dispenser orifice. When the pusher is pressed, the main piston rises in the main cylinder of the pusher, thereby causing the differential piston to slide in leaktight manner inside the differential cylinder. This compresses the spring: the differential piston then moves upwards towards the press wall of the pusher. The active sealing lip of the differential piston, which is in direct contact with the fluid, slides in the bottom portion of the cylinder situated below the outlet channel. As soon as the differential piston arrives at the outlet duct, the fluid put under pressure in the chamber is expelled from the chamber through said duct and travels to the nozzle where it is swirled and ejected through the dispenser orifice.
The present invention therefore relates mainly, but not exclusively, to that type of dispenser member, better known under the term “pusher-pump”. The present invention relates still more particularly, but not exclusively, to dispenser members of the pusher-pump type that are used as samples. Under such circumstances, the dispenser member is of small size and of small capacity and is mounted on a small-sized reservoir, referred to herein as a “flask”. The flask is generally made of drawn glass, but may also be made of plastics material, or of metal. In the broad field of samples, and more particularly in the field of perfumery, samples of perfume are often presented in the form of a glass flask provided with a stopper. The stopper may be made in two portions, namely a base portion secured to the flask at its opening, and a stopper portion that is removably mountable in leaktight manner on the base portion.
The user sees immediately that the sample comprises a reservoir portion, a base portion, and a stopper portion. The base portion provides the interface or the junction between the stopper portion and the reservoir portion.
In general, the base portion and the stopper portion are made of inexpensive plastics materials which are generally translucent or transparent. It is therefore possible to see through the base portion and/or the stopper portion.